Table of Contents
Introduction
Vitamin D is a fat-soluble vitamin called sunshine vitamin essential for forming bones and teeth. Vitamin D also supports the immune system and aids in keeping the bones stronger, calcium metabolism, and contributes to overall health and well-being. The immune system helps the body fight against invading microorganisms. Vitamin D deficiency results in poor immunity and does not preserve sensitivity to certain invading microorganisms and infections, thus promoting autoimmune diseases.
What Are Vitamin D and Its Analogs?
Vitamin D is a lipophilic secosteroid, a hormone or prohormone that aids in calcium and phosphate metabolism. There are two forms of vitamin D: vitamin D2 and vitamin D3. Vitamin D2 is the ergocalciferol and is made by humans and added to food; on the other hand, vitamin D3 is cholecalciferol which is synthesized by the human body when exposed to sunlight. The optimum levels of Vitamin D in the blood are 20 nanograms per milliliter. The sources of vitamin D are exposure to sunlight, fortified foods (such as milk and cereals), supplements, and fatty fish (like salmon and mackerel).
Vitamin D analogs have more affinity towards vitamin D receptors than vitamin itself. This results in the efficient absorption of calcium, phosphate, and magnesium. In addition, they are used to treat various conditions like psoriasis, osteoporosis, and vitamin D deficiency. Some of the analogs include Calcitriol, Doxercalciferol, Calcifediol and Alfacalcidol. The analogs of vitamin D are generally safe and effective. Some may pose side effects like itching, skin burning sensation, dryness, and redness. The analogs should always be used as directed.
What Is the Role of Vitamin D in Overall Health?
Vitamin D is an essential nutrient that plays an important role in developing and maintaining overall health.
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Vitamin D helps to absorb the calcium in the gut and helps to maintain the harmony between calcium and phosphorus. They are the key components in developing strong bones. Thus preventing rickets (thin deformed bones), osteomalacia (softening of bones), and osteoporosis (weak and brittle bones).
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Vitamin D helps to strengthen the immune system.
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Vitamin D reduces inflammation.
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Vitamin D regulates the cell growth.
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Vitamin D helps regulate the metabolism of glucose.
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Vitamin D helps to regulate hormones and promotes reproductive health in men and women.
Why Is Vitamin D Important for the Immune System?
Beyond calcium and bone hemostasis, vitamin D has an important role in innate and adaptive immunity. Cells of the immune system have the ability to synthesize and respond to vitamin D. Therefore, vitamin D deficiency is more prevalent in autoimmune diseases.
Vitamin D boosts the immune system with the help of cathelicidin and defensins. These two essential proteins are produced in response to vitamin D. These peptides have a direct effect on invading microbes and improve the effectiveness of macrophages that engulf these microorganisms.
Vitamin D also blocks B cell proliferation, differentiation, and immunoglobulin secretion. The T cell proliferation and maturation thus reduce the proliferation of inflammatory cytokines like interleukins and pro-inflammatory cytokines like tumor necrosis factors alpha (TNF- α) and interleukin 6 (IL-6). There will be increased production of anti-inflammatory cytokines like interleukin - 10 (IL-10), which reduces inflammation and innate immunity.
The equilibrium should be maintained to keep up the harmony between the anti-inflammatory and inflammatory cells. Maintaining optimum levels of vitamin D promotes a healthy immune system. It enhances the efficiency of disease-fighting abilities of monocytes and macrophages which protects the body from invading microbes.
Apart from this, a better immune system plays an important role in fertility. Immune tolerance plays an important role in accepting a genetically different embryo. A healthy pregnancy happens only when the regulatory T cells suppress the immune response against the developing fetus.
What Is the Role of Vitamin D in Autoimmune Disorders?
Low levels of vitamin D increase the vulnerability to infections, and the chances for autoimmune disorders are increased. In areas where the sources of sunlight are low, autoimmune disorders are prominent. Due to low levels of vitamin D, the immune system loses its ability to recognize even the body’s own cells and attacks the normal cells, thus resulting in autoimmune disorders like multiple sclerosis (disease of the brain and spinal cord), Rheumatoid arthritis (inflammatory disorder affecting the joints), type 1 diabetes, systemic lupus erythematosus (inflammation of multiple organs) and many more. The immunomodulatory effects of vitamin D suppress the innate and adaptive immune responses that result in chronic inflammation affecting the muscles, brain, spinal cord, or organs.
To treat such conditions, Vitamin D supplements in the form of oil-based capsules are taken in different doses ranging from 5000 - 10000 IU per day. The disease activity lowers when there is an increased intake of Vitamin D or its supplements. The risk or incidence of autoimmune disease is reduced in adults who are taking vitamin D supplements regularly.
What Is the Role of Vitamin D in Fertility?
Vitamin D plays an important role in conceiving a healthy baby. When with optimum levels of Vitamin D, the chances of conception are good, and the success rate of in-vitro fertilization is good. Vitamin D supplementation in women controls the development of uterine fibroids. In men, deficiency of this vitamin results in poor sperm quality and low sperm count with abnormal motility and morphology. Vitamin D deficiency promotes hormonal dysregulation and folliculogenesis in women and low serum testosterone in men this implicates the anovulatory cycle in women and diminished sperm quality and quantity in men. Generally, it takes six to eight weeks for the supplementation to be effective in promoting fertility.
Conclusion
Vitamin D is an important nutrient that is produced by the body by exposure to sunlight. It has various effects on bones, the skeleton, and neuromuscular function. It helps to build the body and enhances overall health and well-being. It strengthens the innate and adaptive immune response, thus keeping autoimmune disorders at bay. More than vitamins, vitamin analogs have potential benefits, be it autoimmune disorders or fertility problems. Lower dosages of the analogs produce better results. However, they also pose side effects when not taken as directed. The side effects are hyperphosphatemia (increased amount of phosphorous in the blood), hypercalciuria (increased calcium in the urine), and hypercalcemia (increased calcium in the blood).
